In all these changes, the elastic demand provided by export markets played a crucial role. Without such export possibilities, areas planted, employment, and agricultural output would have expanded less and mechanization would probably have happened more slowly. (If final demand is very inelastic, mechanization could lead to a reduction in agricultural employment even if extra land is available.) Mechanization can also be induced by labor scarcity arising out of nonagricultural demand for labor (case 2). Production costs rise because wages rise rapidly.
This time lag cannot be explained by lack of engineering knowledge in Europe: the same countries were using mechanical threshers for virtually all their crops and seed drills had already been widely adopted. The difference was that labor was more abundant in Europe, farms were smaller, and the harvesting machines were therefore not profitable.